I've always been amused by the sheer number of Space Age superheroes (particularly Marvel superheroes) who gained their powers though accidental radiation exposure. In fact, most of Marvel's "freshman class" of characters gained their powers from deadly radiation. The Fantastic Four, Spider-Man, the Hulk and (later) Daredevil....along with a host of radiation-charged supervillains. It's the comic fan's recognition of this factor that I think plays the biggest part in the design's success....though the safety sign "stick figures" probably have something to do with it, too. My son had a t-shirt with a similar stick-figure that read "I do my own stunts". It was such a stark, funny design I wanted to see if that sort of thing could apply to comics as well.

Judging from the popularity of the design, I guess it could....which continues to remind me that good designs aren't necessarily gigantic productions with billions of tiny details. In other words, "keep it simple, stupid!"